Bare wood cleaning

I’ve searched around and seem to get mixed answers. So I’m gonna ask. Have a uncle that just remodeled his house and now wants to paint his exterior walls which are bare plywood and battens. Mainly dust, pollen, and mild algae in some spots.
He wants me to quote on washing it before he paints. What cleaner would you guys use?


Don’t have any pictures. Might ride over there this evening and take a look.

Get the dust and algae off and paint it. Make sure the algae is completely gone.

Don’t use SH on wood. Use sodium percarb followed up with oxalic or citric acid to brighten it and restore PH balance.


Thanks for the info. Still haven’t went and looked at the job yet. Dang head cold came on strong Saturday afternoon while doing my parents house. 2 shots later and still kicking me.